I've had a few clients using Safari or Firefox that cannot send their forms because the form always says "invalid date format." This happens even when they type in the date mm/dd/yyyy just like it appears on Google Chrome.
I wish I could include a screenshot here, but check out http://www.rodgerobley.com/wedding-info on chrome, then on safari or firefox, and you'll see what I mean. If you want to send a fake form on both browsers, I'm cool with that too.
Thanks,
Rodger